Engraving machine



`Fuly l, 1941. c. E. MccoY ErAL ENGRAVING MACHINE Filed May 10, 1939 4 Sheets-Sheet l July 1, 1941. c. E. MccoY Erm.

ENGRAVING MACHINE Filed yMay 1n, 1959 4 Sheets-Sheet 2 0. M //lsLsF/v l f. Oef-Rr' r Z Wauw,

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7Min/Mfr July 1, 1941.v C@ E MCCOY ETAL 2,247,761

'ENGRAVING vlvhfxcHINls l Filed May 10, 1939 4 Sheets-Sheet 5 July 1, 1941. c. E. MccoY TAL .2,247,761

ENGRAVING MACHINE Filed May 10, 1939 4 Sheets-Sheet 4 Patented July 1, 1941 ENGRAVING MACHINE Clarence E. McCoy, Western Springs, Oliver M. Nielsen, Chicago, and Edward Obert, Oak Park, Ill., assignors to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application May 10, 1939, Serial No. 272,760

Claims.

This invention relates to engraving machines, and more particularly ito a machine for forming a groove in the periphery of irregularly shaped molded articles at the molding die parting line, which follows a variable path in a plurality'ol planes, to remove the overflow material occurring ethereat. I

In Zelenka Patent 1,904,345, granted ,April 18, 1933, the diiculties encountered in making fa molded article of phenol plastic or similar plas. ztic material in such a way as to provide a nis'hed ornamental appearance at the flash line caused -by the molding dies are described. One method of overcoming these difculties is disclosed in said patent. The present method comprises forming a groove, preferably V-shaped in crosssection, along the flash line of the article for removing the flash or n Without marring the ad-t jacent surfaces. Since the groove is narrow the unpolished surfaces within the groove do not de-l tract from the ornamental appearance of the ar ticle which is produced by the polished surfaces of the mold.

An object of the present invention is to prol vide a practicable and efficient automatic machine for finishing irregularly shaped molded articles wherein the flash or overflow material is removed by engraving a groove of substantially constant width and depth therealong without marring the autogenous finish of the adjacent surfaces.

The invention will be disclosed as applied, for example, to the V-shape grooving of phenol plastic molded ytelephone handset handles molded in such a manner that iiash lines occur along dia-1 metrically opposite sides, spaced apart by cir- 4,cular ends where no flash lines occur, the end portions of each flash line extending substantially vertical to the intermediate portion thereof.

In accordance with one embodiment of the invention, a machine is provided in which a cam operated gear ratchet drive is arranged for intermilttently revolving and longitudinally moving at a variable speed a telephone handset handle in a single horizontal plane past a continuously rotating high speed end milling cutter. In the machine cycle the cutter is moved vertically to follow the flash line, longitudinally, to follow the surface of the article, and pivotally to maintain the angle of incidence with the material at a desired value preferably 90. A V-shaped groove is made in preference to a groove with parallel sides since it does not leave sharp corners which are apt to chip off. With a V-shaped groove, however, it is important that the depth of cut be controlled within close limits in order to prevent undesirable variations in the width of the groove at the surface. By means of cams, the cutter, during the movement of the handle therepast, is engaged with the diametrically opposite portions of the handle in succession and predeterminedly moved in accordance with the variable path of the flash line to cut grooves therealong. Means is provided for substantially stopping the movement of the handle al; points where the path of the cutter has a substantial angle transverse to the plane of motion of the handle while cutting the vertical end portions of ithe liash lines. Mechanism is also provided for slightly moving the cutter, in addition to its main movements, in order to compensate for differences in contour in a vertical plane along the peripheral portions of the handle to be grooved, whereby grooves of substantially constant width and depth are obtained. This mechanism includes a limiting or depth gauge finger which rides on the surface of the handle at one side of the flash lines, the finger being vertical during the grooving of the intermediate horizontal portions of lthe flash lines and being rotated either to the right or left from its vertical position to a substantially horizontal position during the grooving of t'he vertical end portions of the flash lines, the mechanism comprising a sliding plate device which translates the rotary motion of the cutter unit into depth gauge finger rotation.

Other features and advantages of this invention will more fully appear from the following detailed description, taken in connection with the accompanying drawings, in which Fig. 1 is a schematic illustration of an engraving machine embodying the features of the invention as applied to the removal of the overflow material occurring along diametrically opposite surfaces of phenol plastic molded telephone handset handles. For the sake of clearness, the frame work and most of the bearings have been omitted from the drawings;

Fig. 2 is an enlarged side View, partly in section, of a portion of Fig. 1 showing the cutter and motor unit;

Fig. 3 is an end view, partly in section, taken on the line 3--3 of Fig. 2;

Fig. 4 is an enlarged vertical detail section of a portion of Fig. 1;

Fig. 5 is a plan View, on a reduced scale, taken on the line 5-5 of Fig, 2 showing the gauge finger rotating mechanism;

Fig. 6 is a fragmentary enlarged plan View of the cam operated gear ratchet handle shown in Fig. l;

Fig. '7 is a vertical section taken on .the line 'i-I of Fig. 6;

Figs. 8 and 9 are side and plan views, respectively, of a telephone handset handle as it cornes from: the molding dies, the overflow' material occurring at diametrically opposite sides of the handle and which this machine is adapted to automatically remove by engraving a V-shaped groove .therealong, the overflow material being partly removed along one side of Fig. 8 and a groove being shown where the overflow material has been removed;

Fig. l() is an enlarged vertical section taken on the line Iii-lli of Fig. 8 with the compensating and grooving mechanisms, shown fragmentarily in operative relation with a longitudinal peripheral portion of the handle, and

Fig. 11 is a fragmentary plan view, partly in section taken on the line iiil of Fig. 8 of the right end of the handle with the compensating and grooving mechanisms, shown fragmentarily, in operative relation with a vertical end portion of the handle.

drive for the Drive for article and cutter Referring now to the drewings, particularly Fie. l, a constant speed electric motor for driving the machine is indicated at lil. The motor shaft carries a worm il meshing with a worm gear l2 fixed to a vertical main driving shaft I3, which carries at its lower end a cam disk irl. A gear segment Il, pivoted at i8 and carrying a cam follower i9, continuously rides in a cam groove Zii of the disk it. Thus, as the constant speed main driving shaft I3 and attached disk It rotate in the direction of the arrow, the gear segment l'i is given an oscillating motion. Meshing with the gear segment il are gears Z3 and 2li which are operatively connected alternately to driven shafts 25 and 26, respectively, at predetermined periods in the cycle of the machine, by a ratchet drive mechanism 2l, to be p-resently described, which transforms the oscillating motion of the gear segment into a unidirectional one and imparts this last motion to a telephone handset handle 2e to be grooved (Figs. l, 8 and 9), the arrow below the handle (Fig. 1) indicating its direction of intermittent'rotation at a variable speed.

At predetermined intervals in the cycle, to be more fully described hereinafter, it is desirable to vary the rate of speed of the driven shafts 25 and 2S. lllhe shape of the cam groove Z!) of the disk it rotating with the driving shaft i3 is such that at predetermined intervals during the grooving of the handle 23 (Figs. 8 and 9), such intervals corresponding to peripheral flash line portions A of the handle which are at an appreciable angle with respect to the plane of motion of the handle, the cam follower I9, carried by the gear segment Il, will ride onto short dwell portions of the cam groove 2?. During the dwell intervals substantially no angular movement of the segment takes place, which reduces the speed of the driven shafts 25 and 2% to what will be termed hereinafter slow speed. The term high speed will be used to designate other predetermined intervals during the grooving of the handle, such intervals corresponding to peripheral iiash Vline portions B of the handle between the spaced flash line portions A of each flash line and also portions C around the circular ends where no flash lines occur. The

high speed intervals are effected by the cam follower riding onto other portions of the cam groove 2i! displaced from the dwell portions thereof, whereby the gear segment il will be oscillated about its pivot i8 in one direction or the other at a desired speed. rIhis oscillation of the gear segment il, controlled by the displaced cam groove portions, it is obvious, effects the desired high speed rotation of the gears 23 and 25.*-, and accordingly, of the driven shafts i5 and 2d of the ratchet drive mechanism 2l. No attempt has been made in the drawings to show the exact configuration of the cam groove 2S, since it will be apparent, from the above description, how it should be cut to produce the described movements.

The telephone handset handle 23 to be grooved (Figs. 8 and 9) is shown in Fig. l as mounted upon a supporting head or table 3l, both shown in broken outline, the table being slidably and rotatably carried upon a suitable slideway (not shown) fork movement in a single horizontal plane along a predetermined path. The handle 23 is secured to the head SI by suitable chucking means which, for the sake of simplicity, has been omitted from the drawings, since it forms no part of this invention and is not considered necessary to a full understanding thereof. Fixed to the table 3i is an elongated slotted mangle type gear 32 which meshes with a gear 33 fixed to the shaft 25 of the ratchet drive mechanism 2l. The gear 32 is guided during the driving thereof through the gear 33, by a headed pin 3d extending through the slot thereof and fixed to the slideway upon which the table BI moves.

The ratchet drive mechanism 2l. includes the driven shafts 2d and 25 upon which, during predetermined periods, are alternately freely rotatable the gears and 2li, respectively, the gears being out of mesh with each other at all times, as clearly shown in Figs. 6 and 7. Adjacent their lower ends the shafts 25 and (Fig. 7) have fixed thereto gears 3l and 3B, respectively, which are in mesh. The gears 23 and 2:! are supported at their lower surfaces upon the gears 3l and 38. Pivotally secured to and carried in recesses of the. gears 23 and 2d are spring pressed ratchet pawls l!! arranged to enter ratchet notches 42 lformed in the associated shafts 25 and 25. From the arrangement of the pawls 4I, as .shown in Fig. 6, it will be apparent that the gears 23 and 2d will impart motion to their respective shafts only for a particular direction of gear rotation. When either gear is rotating in a direction to cause the pawl carried thereby to drive itsY shaft the other gear is merely idly turning in the same direction upon its shaft, the pawl carried by the latter gear being idle. As shown in Figs. l, 6 and 7, the mechanism is in position to start an operating cycle, the handset handle 28 being supported on the table 3l in position ready to be grooved with the longitudinal center line 0f the gear 32 passing through the axis Vof rotation of the gear 33, its direction of rotation being counterclockwise, as indicated by the arrow. The gear segment Il has completed a clockwise oscillatory motion and is in position to begin its next movement in a counterclockwise direction,Y as indicated by the arrow thereon.

In this position of the mechanism, and assuming that the cam disk I4 is being rotated at a suitable constant speed counterclockwise, as indicated by the arrow thereon, the gear segment Il will first move counterolockwisadue to the cam follower I9 ridinguin a ,particular portion of the cam groove 20, thus causing a clockwise rotation of the gears 23 and 24. Through the pawl 4l of the gear 23 the shaft 25 will be driven in a similar direction and likewise the gear 33, fixed to the shaft 25, the gear 33 meshing with the mangle type gear 32 effecting a counterclockwise rotation thereof, as well as the table 3i and handset handle 28. During this part of the cycle, wherein the gear segment l1 is moving counterclockwise, the gear 24 is moving freely without driving its shaft 26, since its ratchet pawl l is not in driving engagement with its notch 42. It will also be apparent that during this part of the cycle the gear 3l, fixed to the shaft 25 is rotated clockwise and since it meshes with the gear 38 fixed to the shaft 26, the direction of rotation of the latter gear and shaft will be -counterclockwise or in a reverse direction to that of the gear 24 carrying the pawl 4l.

In the continued rotation of the disk i4, the movement of the gear segment l1 is reversed to a clockwise direction, due to the cam follower |9 riding in a particular portion of the cam groove 2li, whereupon the gears 23 and 24 are rotated counterclockwise. Since the pawl l of the gear 24 is in driving position, its shaft 25 will also be driven countercloclkwise and likewise the gear 38 fixed thereto. The gear 38 in mesh with the gear 5l fixed to the shaft 25 effects a clockwise rotation thereof, thus continuing the same direction of rotation of the shaft and that of the table 3| and handset handle 28, indicated by the counterc'lockwise movement of the gear segment il. During this latter clockwise movement of the gear segment Il, in which the gear 23 is rotating counter-clockwise, it will be apparent that its ratchet pawl 4i is idle. Thus, regardless of the direction of movement of the gear segment l, the ratchet drive mechanism 2'! transforms the oscillating motion of the gear segment into a unidirectional onev for the handle 28 and by means of the contour of the cam groove 20 at a predetermined variable speed.

Mechanism for moving cutter Zonlgitudinally A mechanism, which will be termed an upper unit and shown embraced within the'bracket 56 (Fig. 1) includes a frame fragmentarily illustrated by spaced horizontal connecting and bearing bars 47 which, together with all the elements carried thereon, are mounted. asl a unit upon suitable slideways 58 for reciprocatory movement in a horizontal plane along lines parallel to the normal or average position of the axis of the cutting tool. Journaled in the right ends of the bars lll is a driven cam carrying shaft a9, receiving its motion from the driven shaft I3 :by a universal joint connection 50, the latter, it will be obvious, permitting the upper unit to be reciprocated in a horizontal plane, as mentioned above, during the continued rotation of the shaft 49. Journaled in the left ends of the bars 41 for vertical and rotary movement is a sleeve shaft 5I, having rigidly attached at its lower end a horizontally extending plate 52 having formed in its lower surface a dovetail shaped slideway 53 in which is slidably carried an L-shaped bracket 54. Carried by a depending vertical arm of the bracket 54 is an air driven turbine motor unit 55, which constantly drives an end milling cutter 55 in the operation of the machine. The motor unit 55 is connected to a compressed air supply source (not shown) by a iiexible connection 51.

A compression spring 53, surrounding a headed screw 59 and interposed lbetween the vertical arm of the bracket 54 and a depending flange 60 attached to the plate 52 normally acts to slide the bracket 54 and the elements carried thereby forward. The screw 59 has a sliding t in the iiange 60 of the plate 52 and its head acts as a stop member to limit the forward movement of the slidable bracket 54, in the slideway7 53 of the plate 52 when the motor unit 55 is in a normal or retracted position, as shown in Figs 1 and 2f, The purpose of yieldably slidably mounting the motor unit 55 upon the reciprocably mounted upper unit will be described hereinafter.

In the operation of the machine, diametrically opposite molding liashes or fins 64, one being shown in the process of removal in Fig. 9, are cut from the sides of the handle, and V-shaped grooves 6l, shown in broken lines in Fig. 9, are cut successively in the handle along the lines of the removed fins. Since the circular ends of the handle do not have to be grooved, the rotating cutter 56 is not in contact with the handle during the rotary movements of the circular ends past the cutter. In timed relation with the intermittent rotation and longitudinal movements of the handle during the grooving cycle, the upper unit is slid rst slightly forward to contact the approaching n 54 at one side of the handle and continues, in contact therewith, until the groove 61 is completely formed therealong, whereupon the upper unit is retracted to withdraw the cutter from the handle and remains withdrawn until the approaching 1in 64 at the opposite side of the handle is in position to be cut. Upon completion of the grooving of the handle, the upper unit is slid slightly rearward, or to the right, to the position shown in Figs. 1 and 2, so that the rotating cutter 5S will be withdrawn from the handle during the removal or reloading operation. Further, it is necessary during the intermittent longitudinal movement of the handle 28 past the cutter 56, during which peripheral n portions B, intermediate the vertical end iin portions A, (Figs. 8 and 9) are grooved and during which grooving the handle has 4been rotated 90 from its position during the removal or reloading operations, that the cutter be moved alternately inwardly and outwardly relative to the longitudinal aXi-s of the handle in order to maintain the cutter in predetermined operative contact with the peripheral surface of the handle, which is of varying contour, so that a substantially uniform width and depth of cut will be formed therealong in accordance with its physical shape. Also, automatic means, to be described hereinafter, is provided for slightly moving the motor unit 55 and thereby the cutter 56 independently of and upon the upper unit to compensate for small irregularities in the physical shape of the handle from that desired along the portions being, grooved and al-so to compensate for differences in curvature in a vertical plane therealong.

For effecting the described main reciprocatory movements of the upper unit the cam shaft 49 carries a cam 68 having a peripheral cam face upon which constantly rides a cam follower 69 mounted in a fixed support 1i). In the operation of the machine one handle is completely grooved during each rotation of the main driving shaft I3 and, therefore, the cam v$83 is provided with two substantially identical opposite cam face portions. Since the cam makes vone revolution for eachrevolution of the handle 28, during which the handle is completely grooved, it will be apparent that each half of the cam will effcct similar desired movements to the cutter 55 alongV the portions A and B of each half of the handle. A compression spring 'li is arranged to constantly urge the upper unit to the right to maintain the cam 63 at all times in contact with thefollower 5S.

Mechanism foi` angularly adjusting cutter In order to maintain the cutter 55 at right angles to the surface of the handle 28 during the grooving thereof along the n portions A and B (Figs. 8 and 9) while the handle is moving longitudinally, which is desirable in order to produce a substantially uniform groove 6l along each half of the handle, means is provided for turning the cutter 55 and the motor unit 55 as a unit about thev longitudinal axis of the sleeve shaft 5| in accordance with the varying contour of the handle so that the cutter will constantly be positioned substantially at right angles to the surface being grooved, the point of the cutter being substantially coincident with the aXis of the sleeve shaft.

The turning of the cutter 55, as above described, is controlled by a cam 'l which is fixed to Vthe cam shaft-49, the cam ybeing formed with a peripheral cam face. Constantly riding on the cani face is a follower 'l5 mounted on one end of a spring pulled lever il pivoted on the lower end of a stud shaft l fixed to the upper bearing bar 4l. The opposite end ofthe lever 'Il has formed thereon a gear segment 8l which meshes with a gear 52 fixed to the sleeve shaft 5I.. The cam lli, since it is carried on thel shaft 59, is rotated in timed relation with the rotary and longitudinal movements of the handle 28 and the cam face is of such contour, being formed with two substantially identical cam face portions, that during the periods when the handle is moving longitudinally the motion imparted to the follower 'i6 riding on the cam face will be transmitted by means of the lever Ti, gear segment 8i and gear 82 to the sleeve shaft 5I, which will receive the necessary oscillatory movements for turning the bracket 54 and cutter 55 to maintain the cutter substantially at right angles to the surface being grooved.

Mechanism for vertically adjusting Gatter Since the handle 2S, during the grooving operation, moved in a single horizontal plane and the overiiow material 5&1. to be removed therefrom constitutes a path in which the portions A vary substantially from the portions B, as clearly shown in Fig. 8, it is necessary that the cutter be intermittently elevated and lowered in order that it may follow the variable path of the overflow material on the handle as it moves therepast.

For controlling the elevating and lowering of the cutter as above described, a cam 83 is fixed to the cam shaft 9, which makes one revolution to one revolution of the handle 23. This cam has a peripheral cam face which is constantly engaged by a follower 85`mounted on one end of a spring pulled lever 88 pivoted on the upper end of the stud shaft 1B. The opposite end of the lever 8S has formed thereon a gear segment 89'which meshes with a gear 90 freely surrounding the sleeve shaft 5I and suitablysupported in a xed horizontal plane. Fixed to and extending upwardly froml the gear is a sleeve having an annular cam face 9| abutting a similar cam face 92 on a sleeve 95 freely surrounding the shaft 5i. At its upper end the sleeve shaft 5I is provided with a flange 95 which normally rests on the upper end of the sleeve 95 so that in an upward movement of the sleeve the shaft will also move therewith, the sleeve at all times being fixed from rotary motion by a stationary pin 91 slidably engaged in an elongated slot in the periphery of the sleeve. The cam face of the rotating cam 83 is of such contour, being formed with two substantially identical cam face portions, and the cam is so timed that during the periods when the handle 23 is being grooved along the portions A and B (Figs. 8 and 9) .the motion imparted to the follower 35 riding on the cam face will be transmitted by means of the lever 8S, gear segment 8S, to the gear 5i?. Thus an intermittent rotary motion in alternate directions at suitable rates of speed is imparted to the gear @Band through the cooperating annular cam faces 9i and 92 on the gear 95 and sleeve 95, respectively, the shaft 5l, which is engaged by means of the flange 96 thereof with the upper end of the sleeve, is rst raised and then lowered by gravity to cause suitable movements of the cutter 56 in an up and down direction to follow the path of the overflow material. It will be noted that in the particular article to be grooved, as disclosed herein (Fig. 8), the vertical fin portions A at one end are longer than the portions A at the opposite end thereof. This necessitates a greater rise of the cutter when working on the longer fin portions A and it is to be understood that the contour of each identical cam face portion of the cam 83 is such that the desired movements of the cutter are effected.

The peripheral face of the gear 82 on the shaft 5l is of such width that it remains in operative engagement with the gear segment 8l during the raising and lowering of the shaft to position the cutter Elias just described.

Means for compensating the movement of cutter to cnt a groove of substantially uniform width and depth Other means, previously mentioned, are provided for automatically effecting slight additional movements to the motor unit and thereby the cutter independent of the movements effected by the .cam 68 to compensate for slight variations from the desired physical shape of the handle.

These means are in addition to the main reciprocatory movements imparted to the motor unit 55 and thereby the cutter 55 during similar movements of the upper unit effected by the cam 5&3, described hereinbefore, so that the cutter will be maintained in predetermined operative contact with the peripheral surface of the handle 28 in laccordance with an average or tolerable physical shape and thereby cut a groove 61 of substantially uniform width and depth therein while removing the molding flash or fin @il therefrom.

Theseslight variations in the shape of the handles 28. are due to Various causes, such as small differences in degrees of shrinkage or warpage, while cooling, after coming from the molding dies, or slight variations in the dimensions of differentv sets of dies, where more than one set of dies are used to produce the required output. 'I'he slight additional compensating movements of the cutter 56 are permitted by the yieldable slidable mounting of the motor vunit 55 upon the plate 52, hereinoefore described, and cooperating limiting or depth gauge means, to be presently described, which rides upon the peripheral surface of the handle closely adjacent to one side of the cutter 55. The use of the foregoing means, generally described, for effecting small movements of the cutter to take care of slight variations from the desired average physical shape of the handle 23 makes it necessary to provide additional cooperating means for giving the limiting or depth gauge finger compensatory movement to allow for predetermined extreme differences in contour in a vertical p-lane which are encountered around the periphery of the handle. Unless these slight additional compensating movements of the cutter are effected a noticeable variation in the width of the groove will occur if cut along a fixed average path controlled by the cam 58 alone.

The additional horizontal reciprocatory movements of the cutter 55 upon the upper unit in order to form a groove 51 of substantially uniform width and depth in the handles, as above described, are controlled by the following mechanism: Fixed to the driven cam shaft 49 is a cam 95 having a peripheral cam face formed with two substantially identical cam face portions to correspond with identical operations effected on opposite sides of the handle, upon which constantly rides a follower |52 mounted on one end of -a spring pulled lever |53. The opposite end of this lever has internal helical gear teeth |134 (Fig. 4) engaged with similar teeth formed on the upper end of the non-rotary sleeve S5. The follower |52 is slidably mounted on a pin attached to the lever |63 whereby the follower will remain in constant engagement with the cam face during vertical movements of the shaft 5| controlled by the cam 83, during which movements the sleeve 95 is moved upwardly and down.- wardly and carries the lever |53 with it. Extending freely through the sleeve shaft 5I is a rod |55 which at its upper end projects through an apertured bracket W5 secured to the upper face of the lever |53. A nut |08 adjustably threaded onto the projecting upper end of the rod |135 and resting on the upper face of the bracket |55 is effective normally to support the rod in a desired vertical position upon the upper unit.

The lower end of the rod |55 is operatively connected to the outer end of a horizontal arm of a bell crank lever |59 (Figs. 2 and 3) pivoted at i l5) to ears on the horizontally slidable bracket 54 which supports the motor unit 55. The connecticn between the rod |05 and the arm is such that during vertical movements of the rod the lever |59 will move about its pivot H5, while permitting the arm to move longitudinally when the slidable bracket 5!! is moved relative to the upper unit in a manner presently to be described. Attached by screws IH to the left end face of the motor unit 55, as viewed in Fig. 2, is a flanged sleeve H2. Surrounding and longitudinally slidable as well as rotatable upon the sleeve H2 is a sleeve H3 formed with an annular channel IIS. A vertical arm of the bell crank lever |09 is bifurcated and the lower ends of the furcations carry rollers Hl (Fig. 3) which ride in the channel H5 of the sleeve H3.

Disposed directly above the cutter 55, with the parts in the sleeve H3 within a slot thereof. The depth gauge nger ||8 is of such length and arrangement that when the cutter 55 is engaged with the periphery of the moving handle 28 the nger rides on the peripheral surface thereof closely adjacent the upper side of the path of the cutter and determines the depth of the grooves 61.

The sleeve H3 at its right end, as viewed in Fig. 2, wherein the motor unit 55 is shown in a normal position with the cutter 56 retracted from cutting relation with the handle 28, is slightly spaced as indicated at H9 from the flange of the sleeve H2. The space H9, which occurs at all times in varying degrees, provides for a limited longitudinal movement of the sleeve H3 with its attached finger l i8 upon the motor unit 55. The purpose of rotatably mounting the sleeve H3, which carries the gauge nger H8, upon the sleeve I I2 will be described hereinafter.

In Figs. l0 and 11 there are shown extreme differences in. contour in a vertical plane which are encountered along the peripheral portions of the handle 28 while being grooved. The handle 28 is shown fragmentarily in vertical cross-section in Fig. 10 and substantially horizontal cross-sectionV in Fig. 1l. Fig. l0 represents a condition along one of the horizontal peripheral fin portions B midway between the vertical fn portions A and, therefore, the limiting or depth gauge finger H8 is vertically disposed, while Fig. 11 represents a condition along one of the vertical fin portions A (Fig. 8) and, therefore, the finger has been rotated approximately 45 by a rotary movement of the sleeve H3 by means to be presently described. In both cases the finger H8 is riding on the surface of the handle under the action of the yieldable slidable mounting (Fig. 2) of the motor unit 55 and the cutter 55 is cutting a symmetrical groove 5l of the desired dimensions. It will be apparent that within the range of movement of the motor unit 55, permitted by the yieldable slidable mounting, small differences in dimensions of the handle from the tolerable average in the surface along the path of the cutter 55, as shown in Figs. v10 and l1, will result in movements of the cutter varying with differences in dimensions and controlled by the limiting engagement of the nger with the handle, thereby producing a symmetrical groove 5l of the desired dimensions.

It is obvious that to cut substantially the same depth of groove under each of the conditions represented.' by Figs. l) and ll, the limiting nger H5 must be back of the point of the cutter 55 in the condition disclosed in Fig. 10 and forward of the point of the cutter in Fig. 11. The space l l@ hereinbefore described between the flange of the sleeve i 2 and the adjacent end face of the sleeve H3 permits the movements of the nger H5 relative to the point of the cutter 56, as shown in Figs. l0 and l1. That is, the position of the finger H8, as a whole, must be -capable of being given a movement with respect to the motor unit 55 and the cutter 55 in a direction parallel to the axis of the cutter.

Since the bell crank lever |69 is pivoted to the slidable bracket 55 at Il) and thereby at a point integral with or fixed relative to the motor unit 55 and cutter 55, it is obvious that any rotary motion of the lever will change the position of the finger relative to the motor unit and cutter. It is to be understood that any independent movement of the gauge finger H8 will not transmit any rotary motion to the bell crank lever |89, due to the latter being pivcted at H to the bracket 54.

The positive movements of the limiting nger H8 to position the finger relative to the motor unit 55 and cutter 56 during the cutting of the groove 51 in the handle 2B to compensate for eX- reme differences in vertical contour encountered around the periphery of the handle, as illustrated in Figs. 10 and l1, and described hereinbefore, are effected by the cam 58. At predetermined intervals during its rotation the cam 98 causes slight rotary motion in opposite directions,to be imparted to the spring pulled lever |03 carrying the follower |02. By means of the internal helical gear teeth |54 of the lever engaged with the similar teeth of the non-rotaly sleeve 95 surrounding the sleeve shaft 5|, vertical movements are imparted to the lever and v'through the attached bracket |85 engaging the nut |58 on the vertically movable rod V|55 the latter is moved upwardly and downwardly, thus rocking the bell crank lever |58 about its pivot H0 on the yieldable slidable bracket 54, supporting the motor unit 55 and cutter 56, the lower end of the rod |55 being connected to the horizontal arm of the lever. tft will be obvious that under the control of the cam 98 the gauge finger ||8 is adjusted toward and from the point of the cutter 58 in a direction parallel to the `axis of the cutter to allow for extreme differences in contour in a Vertical plane occurring along the opposite peripheral portions of the handle 28 to be grooved. Thus the cutter 55 will be so limited in its movement toward the handle, at portions of its varying peripheral contour, in removing the molding flash or n 54 therefrom, that a groove of substantially uniform width and depth will be formed therein. Briefly, therefore, it is seen that the cutter 5S has a program controlled Vertical movement, a program controlled swinging movement, two program `controlled longitudinal movements, a third type of automatic longitudinal movement controlled by the article itself through the gauge finger 8 riding thereon. The program controlled movements are, of course, predetermined substantially in accordance with the ideal desired shape and size of the molded article, while the gauge ringer controlled movements are The rotation ofthe nger H8, as above described, .is eiected by rotating the sleeve H3 upon which the nger is carried in the following manner. Referring to Figs. 2, 3 and 5, an irregular shaped horizontal plate arranged below the forward end of the motor unit 55 is siidably mounted for reciprocatory movement in a direction at right angles to the longitudinal ,axis of the cutter 55 when the motor unit 55 is in position to start an operating cycle, as shown inFigs. 1, 2 and 5. The plate |25 is slidable upon a pair of spaced pads |25, fixed :to the frame of the` machine (not shown).

Formed longitudinally in opposite long arms of the plate |25 are a pair of alined spaced slots |28 through which extend headed and shouldered pins |29 i'lxed to the pads 125, the slots and pins serving to guide the plate |25 in its reciprocatory movement. Also formed in :the plate |25 is a slotl' which extend-s at right angles to the former slots and is aligned with the longitudinal `axis of the `cutter 56 when the cutter is in a retracted .position adjacent the circular end of the handle 23. Attached to the motor unit bracket 54 is a depending pin |33 which extends through the slot |313. Fixed to and depending from the sleeve H3 which is rotatable upon the sleeve |E2 attached tothe motor unit is a pin |35 which also extends through the slot |35.

for taking care of variations from the ideal which f occur in practice.

Means for rotating gouge finger Since the gauge finger |i8, carried on the rotatable sleeve M3, is vertical during the grooving of the horizontal portions B of the ns 54 and is riding on `the peripheral surface of the handle above the path ofthe nn, in order to serve as a limiting or depth gauge, it is necessary to rotate the finger approximately 415 either clockwise or counterclockwise during the grooving of the substantially vertical end portions A of the fins 55 in order that the nger may still ride on the surface of the handle at the side of the path of the iin. If these rotary movements of the nger This, it Will be apparent, would depth gauge in order that grooves 6'! of substantially constant Width and depth may be cut.

Referring to Figs. 2, 3, 5 and ll, particularly to Fig. 5, it will be assumed ,that during a cycle of the machine the handset handle 28 has been rotated counterclockwise from the full line position to the dotted line position to begin the grooving of one side of the handle. Also that in timed relation therewith, the motor unit 55, through the combined action `of the cams 58 and l5, has been advanced and with it the cutter 55, shown fragmentarily, from the full line position thereof to the dotted line position wherein it is shown as contacting the lower end of t-he rst vertical portion- Al ofthe flash line to be grooved and is disposed at right anglesl thereto. This is clearly illustrated in Fig. ll. This turning of the cutter is effected by an angular adjustment as a unit of .the motor unit 55 and the cutter carriedv thereby about the axis of the sleeve shaft 5i, in the manner previously described, the point of the cutter being substanti-ally coincident with the axis of the `sleeve shaft.

During the angular adjustment of the motor .unit 55 the pin |33 xed to the bracket 54 is like- .the plate is slid upon the rpads |25 along a rectilinear path to lthe dottedline position thereof. In this movement of the plate |25 the pin |35, which also extends through the Yslot Iof the plate |25, isV also moved along an arc-shaped path and since this latter pinis carried by the rotatablesleeve ||3 carrying thedepth or gauge nger ||8 thesleeveand linger are rotated in a counterclockwise direction, as viewed in Fig. 3, so that the finger will bear against the 4surface of the handle at the side of the vertical path of the. fin B4 along theportion A. The opposite .vertical sides ofthe slot` |55 are so formed. asindicated ,at |35 in Fig. 3, as to, provide .workable clearances for the pin 25 as it is rotated in opposite directions about theraxis of the sleeve H3. As the cutter 55 moves upwardly, following the vertical path of the rr portion A, under the action of the cam 83, and nears the horizontal 1in portion B, the cam 'I4 acts to angularly adjust the motor unit 55 and nally returns ,the slidable plate IE to the full line position shown in Fig. 5 in which position .the finger II8 wili be in its vertical position again. At the opposite end of the handle 28 when the horizontal finy portion B1 has been grooved the same movement of the fin-- ger H8 occurs except in a clockwise direc-tion., as viewed in Fig. 3, during the grooving of the vertical fin portion A. On .the opposite side of the handle 28 the same movements of the finger H8 occur as described above in connection with the grooving of the first side of the handle.

Operating cycle It it believed, from the foregoing description' of the improved automatic engraving machine: disclosed as applied to the finishing of plastic molded telephone handset handles wherein the overflow material is removed by cutting continuous grooves in opposite sides of the handle, that the manner of intermittently revolving and longitudinally moving the handle in a single horizontal plane past a continuously rotating cutter which is predeterminedly moved in a plurality of directions so that it Will follow the variable path of the overiiow material and cut grooves of substantially constant width and dept-h thereat will be clearly apparent. However, it may be well to indicate, by way of summary, what such general operation involves.

It will be assumed, for the purpose of this gen-- eral description, that for each revolution of the main driving shaft I3 the handle 23 receives one complete revolution, during which spaced continuous grooves I'i are out therein by the cutter 55, at the completion of which the handle will be in its normal removal or reloading position. At the same time, the cam shaft 49 and the cams t3. it, 33 and 33 carried thereby are driven at the same speed as the shaft i3 through the universal joint 53. will vary between high and low speeds through the medium of the ratchet drive mechanism 2l, controlled by the cam groove 23 of the disk I6, in the manner hereinbefore described. It is to be understood that when the shaft 25 is being driven at either high or low speed the handle 23 is likewise driven by the gear train 33 and 32. Also, it will be assumed that the cams I4, 58, ifi, 83, QI, 92 and 38 have all been formed as well as adjusted relative to each other upon their respective shafts to time correctly the periodic movements to be effected thereby.

Beginning the cycle of operation with the continuously rotating cutter 55 retracted slightly from theperipheral surface of the handle 28 which has just been loaded onto the sldable and rotatable table 3l, as shown in Figs. 1 and 2, and which is held. stationary for a predetermined interval during the removal or reloading operation by a movement of the gear segment I'I under the control of the cam groove 20, of the disk I4 fixed to the constant speed main driving shaft I3, all in the manner previously described, the grooving of the handle immediately follows.'

In the continued rotation of the shaft I5 the table 3I is first given a counterclockwise rotary movement of 90 and, consequently, the handle 23 carried thereon is given a similar movement. In timed relation with this rotation of the handle the cams 33 and M effect an advancement of the motor unit 55 and thereby the cutter 56 into operative contact with the lower end of the vertical portion A of the n 64 at the right end of the handle (Figs. 5 and 9). During the angular adjustment of the cutter 55, effected by the The speed of the shaft 25,

cam 14, to the position shown in Fig. 11, in order to maintain the cutter at right angles to the surface of the handle being grooved, the limiting finger I I8 carried by the sleeve I I3 is rotated approximately 45 in a counterclockwise direction (Fig. 3) from its initial vertical position to the position in Fig. 11, by the means previously described, which includes the pin |33 carried by the motor unit 55 and the sliding plate I25, so that the nger will ride on the surface of the handle at one side of the substantially vertical portion A of the fin 64. In timed relation with the engagement of the cutter 56 with the portion A of the iin 64 the cam 83 in the manner previously described causes the cutter to travel upwardly following the path of the iin E4 during which cutter movement the handle is substantially stopped or reduced to slow speed which is effected by the cam groove 23 and associated mechanism previously described. Thereafter the handle 28 is intermittently longitudinally moved and revolved counterclockwise past the cutter at high speed except at the vertical portions A of the pin 'I4 at which points it moves at slow speed, the cutter 5S being predeterminedly moved during thecomplete rotation of the handie to cause it to follow the Variable path of the continuous spaced fins 54 at opposite sides of the handle to remove them and form grooves El therealong which are of substantially constant width and depth.

In timed relation with the approach of each of the vertical 1in portions A to the cutter, the cam 'I4 acts to angularly adjust the cutter in the manner previously described and simultaneousli therewith the limiting finger I I8 is rotated either counterclockwise or clockwise, as required, so that it will at all times ride on the surface of the handle at one side of the path of the groove E1 being formed, thus keeping the finger from coming in contact with the n 64 or with portions of the groove previously out. The cutter 55, as previously described, is in a retracted position through the action of the cam 38 during the rotary movements of the circular ends of the handle 28 past the cutter.

At the termination of one complete revolution of the table 3|, the handle 23 is back at its normal position, as shown in Fig. 1, the table thereafter remaining stationary for a predetermined interval under the control of the cam groove Z3 of the rotating disk I4, to permit the removal of the grooved handle from the table 3I and the mounting of a handle to be grooved thereon. As the table 3l comes to a halt, the cutter 55 is retracted from the grooved periphery of the handle, and the cycle of operations is completed.

It is evident from the herein detailed description, that a very practicable and efficient automatic engraving machine is provided whereby peripheral molding fiash lines occurring along diametrically opposite sides of irregularly shaped plastic molded articles at the molding die parting line and following a variable path in a plurality of planes may be expeditiously and efliciently removed and continuous grooves of substantially constant width and depth formed therealong without marring the natural finish of the adjacent surfaces ofthe articles. Also, that by means of the compensating mechanism for positioning the cutter to take care of slight variations from an average or tolerable physical shape of the article, due to the various causes hereinbefore mentioned, and to extreme differences of contour in a vertical plane which are encountered along the sides of the article, grooves of maximum general uniformity may be formed in articles varying within limits from an average physical shape.

While the invention has been described with reference to a particular embodiment thereof for electing the grooving of plastic molded telephone handset handles, it will be understood that it may be embodied in various forms, and is capable, ofl other applications limited only by the scope of the appended claims.

What is claimed is:

1. In a machine for forming a groove following a path having portions extending at a substantial angle to each other inthe surface of an article, a forming tool, means for relatively moving said tool and article, a gauge rotatable about the axis of the tool and riding on the article surface at the side oi the tool operatively interconnected thereto to control the depth of the groove, and means for rotating the gauge in timed rciation to the relative movement of the tool and article'so that the gauge constantly rides on the article surface at the side of the tool.

2. In a machine for forming a groove following a path having portions extending at a substantial angle to each other in the surface of an article, a forming tool, means for relatively moving said tool and article at a variable speed whereby the groove is formed at a substantially constant speed, a gauge rotatable about the axis of the tool and movable in a rectilinear direction riding on the article surfaceat the side of the tool operatively interconnected thereto to control Vthe depth of groove, and means for rotating and rectilinearly moving the gauge in timed relation to the relative movement of the tool and article so that the gauge constantly rides on the article surface at the side of the tool.

3. In a machine for forming a groove following a variable path in a plurality of planes and having portions extending at a substantial angle to each other in the surface of an article, a forming tool, means for relatively moving said tool and article to cause a traverse of the surface by the tool, means for eiecting additional predetermined relative movements in a plurality of directions between the toolrand article simultaneously with the rst mentioned relative movement to form a groove following a variable path in a plurality f planes in the surface of the article, said i gauge rotatable about `the axis of the tool and ridingon the article surface at the side of the tool operatively interconnected thereto to control the depth of the groove, and means for relatively rotating the gauge and article in timed relation to the relative movements of the tool and article so that the gauge constantly rides on the article surface at the side of the tool.

4. In a machine for forming a groove following a variable path in a plurality of planes and having portions extending at substantial angles to each other in the surface of an article, a forming tool, means for moving the article past the tool at a variable speed whereby the variable path groove is formed at a substantially constant speed, means for moving the tool in a plurality of directions simultaneously with the movement of the article past the tool and in timed relation with the variable speed thereof to form a continuous groove following a variable path in a plurality of planes in the surface oi the article, said tool moving means including means for bodily moving the tool angularly to maintain its angle of incidence with the surface to be grooved at a desired Value, a rotatable and reciprocatory gauge riding on the surface of the article at the side of the tool operatively interconnected thereto to control the depth of the groove, and means for rotating the gauge in timed relation to the angular movements of the tool so that the gauge constantly rides on the surface of the article at the side of the tool.

5. In a machine for cutting a groove following a variable path in a plurality of planes and having portions extending at substantial angles to each other in the surface of an article, a cutting tool unit, means for moving the article past the cutting point of the tool at a variable speed whereby the variable path groove is cut at a substantially constant speed, means for moving the tool unit in a plurality of directions simultaneously with the movement of the article past the tool and in timed relation with the variable speed thereof to cause the tool to cut a continuous groove following a variable path in a plurality of planes in the surface of the article, said tool unit moving means including means for bodily moving the tool unit angularly about an axis coincident with the point of contact of the tool with the surface to be grooved to maintain its angle of incidence therewith at a desired value, a gauge riding on the surface of the article at one side of the tool point operatively interconnected thereto to control the depth of cut, and means operatively interconnecting the tool unit with the gauge responsive to angular movements ci the tool unit for rotating the gauge so that it constantly rides on the surface of the article at said one side of the tool point.

CLARENCE E. MCCOY. OLIVER M. NIELSEN. EDNARD OBER'I. 

